GYRO-COMPASS 


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Copyright,  1920 

THE  SPERRY  GYROSCOPE  COMPANY 

Brooklyn,  N.  Y..  U.  S.  A. 


DESIGNED.  ENGRAVED 
AND  PRINTED   BY 


ROBERT  LSTILLSON 
COMPANY-NEW  YORK 


THE 


PERRY 


Gyro-Compass 


The  Sperry Gyroscope  Co. 

MAIN     OFFICE     AND     FACTORY 

MANHATTAN      BRIDGE     PLAZA. 
■      BROOKLYN, N.Y.    • 


■"''^'•'-Tr'vr^ 


L-r»fc.->jnctt*i;«i?f«%:*«i'-»-i.f*iie^f<y%.yyM. 


MfiCFANICS    DEPT, 


VKS77 

S7^ 


Engineering 
Library 


icconccooocs 


The  S perry 


Qtro-Compass 


^rvnrrvv'^  ■^fflf?  ■f*-wrT"f<v<^f<'fW'«V''rtCT-r«yvcg-r 


Man's  first  venture  in  shipbuilding  was  the  Raft 


iRa.T 

■■■SI 


THE   SPERRY    GYROSCOPE   COMPANY 


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—    REPRESENTATIVES 


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MilaD 


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OTTO  PLATOU 

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25  Broad  Street 

New  York 


^i>s^  yu,\ 


The  S perry 


nfCtVfyrtVlJ.yv^ymi t^-fvci.  . ^'L-..-t\-^-i.-iYvvr-ryfyf<y 


QfRO-COMPASS      f)^ 

w  / 


An  inflated  oz-skin  Balsa  of  earliest  timea 


THE 

SPERRY  GYROSCOPE 

COMPANY 

'^ 

Manufacturers  of 

gyro-compasses  gyro  ship  stabilizers 

gun-fire  control  apparatus  navigational  instruments 

Naval  and  Commercial  Searchlights 


'■•'***i  Tf  ■"'■—'^^r*' 


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iwuMrmwouBCBcu 


The  S perry 


^^^^ 


.^>mi 


PiB 


TLt  aiuifiit  |■;^;>l.tlaIJ^  Imilt  Iniultsuf  ruslu-.- 


GfRO-COMPASS 


Putting  the  Earth  to  Wpj'k  ;  ;: 

|HEN  the  earth  was  thrown  off  from  the  si'm. 'and,. "(j<fltiitHB,rt'ced  rotating 
about  its  own  axis,  there  was  developed  a  force  generated  by  the 
earth's  rotation.  For  countless  centuries  this  force  has  been  at  work, 
hut  no  one  has  ever  been  able  to  harness  it  to  serve  the  purposes  of 
man.  But  now,  through  the  efforts  of  Foucault,  Hopkins,  Sperry, 
and  other  noted  scientists,  this  force  has  been  put  to  work.  It  serves 
to  direct  a  thousand  ships  in  their  courses. 

Of  course,  this  is  not  the  only  force  which  has  been  used  to  guide 
ships.  Since  1297  A.D.  mariners  have  used  magnetic  attraction  as  the  force  by  which 
to  guide  their  vessels.  For  centuries  seafaring  men  sailed  only  in  wooden  ships,  and 
were  therefore  satisfied  with  the  magnetic  compass.  Then  came  steam  and  steel. 
Navigation  then  instead  of  being  a  hit  or  miss  game  of  chance  became  the  exact  art  of 
directing  a  ship  by  the  shortest  possible  course  in  the  quickest  possible  time. 

Now  that  ships  cost  millions  of  dollars  to  build  and  thousands  of  dollars  per  day 
to  operate,  time  has  become  the  most  essential  element  in  navigation.  The  develop- 
ment of  ships  from  the  sailing  vessel  to  the  ocean  greyhound  has  been  one  of  the  marvels 
of  modern  times.  But  the  development  of  the  magnetic  compass  has  not  kept  pace 
with  the  development  of  the  ships  which  rely  upon  it.  Many  of  the  great  trans- Atlantic 
liners  are  guided  by  practically  the  same  type  of  compass  as  that  which  Columbus 
used  on  the  Santa  Maria.  The  compass  on  the  wooden  Santa  Maria  pointed  to  magnetic 
north  with  a  fair  degree  of  accuracy,  but  the  compass  on  the  steel  greyhounds  must 
contend  with  many  distractions. 

For  years  magnetic  compass  designers  spent  their  efforts  to  produce  compensa- 
ting devices  that  would  annul  the  effects  of  all  external  influences,  so  that  the  magnetic 
compass  would  be  free  to  indicate  only  the  direction  of  the  earth's  magnetic  lines. 
Very  little  has  been  done  to  improve 
the  compass  itself — it  still  depends 
upon  the  attraction  of  the  Magnetic 
North  Pole.  The  Sperry  Gyro-Com- 
pass  differs  in   principle  from  any 
other  compass.  It  is  not  magnetic.  It 
derives  its  directive  force,  not  from 
magnetic   attraction,   but   from  the 
earth's  rotation. 

There  is  certainly  a  crying  need 
for  this  new  type  of  compass.  A  ship 
now-a-days  costs  millions  of  dollars 
and  carries  cargoes  usually  equal  in 
value  to  that  of  the  ship.  It  has  been 

liiiiiiiit.'  Ki  fji  iilrr 
■  m  1  |'|MT  Hrlclpi- 


''7'^^^''^'^"^^  ^  r   T-~' '  '. 


'r^y-^^-rtrrr^-r 


The  S perry 


.&R0-C0MPASS.  f)^ 


r.yyT:pypi7«-->xx-f<V-C'fTVV-yx^^ 


■'^i;3>i»5>^ 


e    -'— ■ :i 

The  Vikings  crossed  the  Atlantic  in  open  slups 


estimated  that  inaccuracies  in,  navigation  attending  the  use  of  the  magnetic  compass 
cause  a  yearly':k)$s  of-.ships;  tp:  the  value  of  $70,000,000.  No  estimate  can  possibly  be 
made  on  the.vfilue.iQf  .U-ves  lost  oh  these  ships. 

Milliong-Bf^d^ilars  are' spent  ieach  year  on  charts,  lighthouses,  buoys,  geodetic  and 
hydrographic  surveys,  and  on  compilation  of  notices  to  mariners.  Notwithstanding  all 
of  these,  ships  must  ultimately  depend  upon  their  compasses  for  their  safety  and 
efficiency  of  navigation. 

Inaccuracies  in  navigation  can  be  eliminated  by  the  use  of  a  reliable  compass.  The 
Sperry  Gyro-Compass  puts  the  earth  to  work.  It  utilizes  a  force  which  is  as  unvary- 
ing as  the  law  of  gravity,  a  force  that  cannot  be  interfered  with  by  any  other  influence. 

How  the  Earth's  Rotation  Is  Utilized 

Any  wheel  rotating  at  a  high  speed  about  its  own  axis,  and  free  to  place  itself  in 
any  plane,  is  called  a  Gyroscope.  The  Gyroscope  is  the  instrument  which  utilizes  the 
earth's  rotation  as  a  force  to  direct  the  course  of  ships. 

Suppose  you  were  to  place  such  a  small  wheel  supported  by  its  axis  upon  a  larger 
wheel  which  also  is  revolving.  The  rotation  of  the  larger  wheel  would  so  influence 
the  smaller  wheel  that  its  axis  would  point  in  the  same  direction  as  the  axis  of  the  larger 
wheel.  Why  this  is  the  case  does  not  concern  us  here.  Let  it  suffice  that  the  larger 
wheel  will  cause  the  smaller  wheel  to  behave  in  this  manner.  This  is  in  accordance  with 
a  natural  law.  This  law  operates  as  unfailingly  as  the  law  which  causes  an  unsupported 
body  to  fall  to  the  ground. 

Suppose  the  larger  wheel  happens  to  be  the  earth,  which  in  reality  is  a  revolving 
wheel.  Suppose  further,  the  small  wheel  is  a  Sperry  Gyro-Compass.  In  accordance  with 
this  natural  law  just  outlined  the  smaller  wheel,  or  Gyro-Compass,  will  point  its  axis  in 
the  same  direction  as  the  axis  of  the  earth,  or,  in  other  words,  to  the  true  or  geographical 
North  Pole.    This  explanation  of  the  principle  of  gyroscopic  motion  is  necessarily  crude. 

The  principle  itself  has  been  estab- 
lished beyond  any  reasonable  doubt. 
It  can  be  proved  by  mathematics  to 
the  satisfaction  of  the  most  exacting 
scientist  and  has  been  demonstrated, 
throughout  the  navies  of  the  world, 
to  practical  seamen. 

The  final  result  is  that  we  have 
a  principle  which  enables  us  to  con- 
struct an  instrument  which  will  place 
itself  in  the  true  geographic  north  and 
south  meridian,  and  that  it  responds 
to  no  influence  or  impulse  other  than 
the  earth's  unvarying  rotation. 

V'ri[wrinf;  \Iaslir 
( '.oiiipass  for  T<'sl 


■CTITTTfTrrTO-rT 


niimfiTrocccnBi 


M''*^*^'i'ri  11 ■■■**WT 


BOO^tv. 


The  S perry 


j^^- 

f--' 


GiTRO-COMPASS 


-t>^^rcv>nt>-v>-.f<i'n.>itm'm 


Galle>'-&lavcs  druve  the  Triremes  of  ancient  Rome 


sou-ni  Pole 
FiauRE  1 

ThI  tABTH  SUEBOUNDED  BY    liOfTATlNG   V/HEaS    AS   iT  APPEARS  lb 
An  iMAGINACY  055ERVEE    LOOKJNG   AT  iT   TliOM  THE   SIDE. 


FlQ'UR.E  2 
TWE    EAUTn   SUUTJOVINDED    BY    ROTATINQ 

Wi-iEELS   A5  IT  Appears   To  An  iMAQiNARt 
Observer,  Loownq   Diuectly   At  The 
50UTH   Pole 


BcaaB 


'liBriiHHft'ruYri  >  'TMnocB 


The  S perry 


<r-eYVf^>^^YV^\-v.-.-Tv.->-fry,T-^-p^--:---i;;rt2- 


•^^TfTccrTr.-^yyn^'^ 


OfRO-COMPASS 


-^-Yi^^vT>^^■^;:i-^^y^.>ryI>:yT-^>^v\^l.x^^-^\x^^L^^-^'^v^Yir^:a:J■^^.^l^^ 


A  War-diip,  "when  knighthood  was  in  flower" 


How  a  Compass  is  Used 


I  HE  purpose  of  a  compass  is  to  indicate  direction.  The  relative 
position  of  the  North  Pole  to  any  point  on  the  earth's  surface  is 
called  North.  We  figure  all  direction  from  this  conception.  This 
geographical  North  Pole  is  called  the  True  North.  About  800  miles 
from  this  True  North  Pole  is  a  spot  which  has  a  strange  magnetic 
attraction.  The  needle  of  the  magnetic  compass,  if  undisturbed  by 
^"  local  influences,  points  to  this  spot,  and  not  to  the  True  North  Pole. 
This  spot  is  called  the  Magnetic  North  Pole.  This  mysterious  attractive  spot  is  not 
stationary.      It  moves  about  from  year  to  year  within  a  wide  circle. 

Inasmuch  as  the  navigator  must  refer  to  True  North,  he  must  determine  the  angle  or 
variation  between  True  North  and  Magnetic  North  as  indicated  by  his  magnetic  com- 
pass. This  determination  is  made  comparatively  easy  by  using  charts  which  express  in 
degrees  the  difference  between  Magnetic  North  and  True  North  for  any  point  on  the 
earth's  surface. 

Such  a  chart  is  shown  in  Figure  3.  Also  on  each  chart  used  by  a  navigator  for  a 
particular  locality  there  is  marked  a  compass  rose  in  which  is  recorded  the  variation  for 
that  exact  spot  as  of  a  certain  date,  and  in  addition  the  rate  at  which  the  variation 
changes  annually,  Figure  4. 

Navigation  along  a  coast  line  where  sights  can  be  taken  on  buoys  or  lighthouses  is 

simple,  and  is  termed  "piloting."   This,  of  course, 
can  be  done  without  the  aid  of  a  compass. 

Upon  getting  to  open  sea  the  mariner  checks 
his  position  in  a  similar  manner,  by  observing 
the  position  of  his  ship  in  relation  to  the  position 
of  the  sun,  moon  or  stars.  Between  observations 
the  position  of  a  ship  is  determined  by  "dead 
reckoning."  The  distance  it  has  traveled  from 
the  last  known  position  is  measured  by  the  ship's 
log  and  the  direction  is  indicated  by  the  compass. 
Very  often  for  days  at  a  time,  owing  to  weather 
conditions,  it  is  impossible  to  get  an  observation 
or  sight  on  a  celestial  body.  During  this  run  the 
navigator  is  dependent  entirely  upon  the  com- 
pass. The  slightest  error  in  the  compass,  due  to 
variation  or  deviation,  in  such  circumstances 
will  cause  the  ship  to  be  miles  out  of  its  course, 
and  the  actual  position  will  be  far  from  the 
calculated  position. 

AwjiiliiiK  Shipmenl 


10 


f.-.r.^y^ff^,r« ->T-fyv^-«T.  ^ot HJrfewtOttXl 


The  S perry 


'^^-'^Tyrp'^^yiTrr''''^^'^^'''^''^"'""'^'^*'^^ 


Gtro-Compass 


(  rusiuliTs  sailed  to  Palestine  in  shipe  like  this 


r- 


Figure  4 


11 


.yccocrcccnBnocnooMt 


The  S perry 


■p«'gg^T'^''<y'9"^'yrf 


Gyro-Compass 


l.V.>,-~^~^~.^ rr.-rr.,-,v^.-->»-or.T«vtvvVT< 


1. 

2. 
3. 
4. 

5. 
6. 
7. 
8. 
9. 
10. 


The  Santa  Maria  carried  Columbus  to  the  new  world 

The  Ideal  Compass 

F  YOU  were  to  conceive  of  a  compass  which  would  be  free  from  all  the 
troubles  and  errors  found  in  most  compasses,  which  would  relieve 
you  of  all  the  worry  and  care  the  present  compass  requires,  a  com- 
pass which  would  be  accurate  and  reliable,  a  compass  which  would 
be  the  Ideal  Compass  under  all  conditions,  you  would  undoubtedly 
conceive  of  a  compass  that  had  the  following  characteristics: 


It  must  point  True  North. 

It  must  free  you  from  the  necessity  of  making  calculations  and  corrections. 

It  must  free  you  from  compensating  the  compass  for  errors. 

It  must  free  you  from  the  burden  of  swinging  the  ship,  or  otherwise  taking  the 

deviation  of  your  compass. 

It  must  not  be  influenced  by  inherent  magnetism  of  the  ship. 

It  must  not  be  influenced  by  any  change  in  the  character  or  disposition  of  the  cargo. 

It  must  not  be  influenced  directly  or  indirectly  by  any  temperature  changes. 

It  must  not  be  influenced  by  the  roll  or  pitch  of  the  ship. 

It  must  not  be  influenced  by  any  weather  conditions. 

In  the  event  of  failure,  or  error,  it  should  give  instant  warning. 


Comparison  of  the  Magnetic  Compass  with  the  Sperry  Gyro-Compass 

Let  us  compare  the  Magnetic  Compass  with  the  Sperry  Gyro-Compass  and  deter- 
mine which  more  nearly  approaches  the  Ideal  Compass. 


True  North 


The  Magnetic  Compass 

The  Magnetic  Compass  does  not  point  to 
True  North,  it  points  to  Magnetic  North, 
which  is  about  800  miles  from  the  True 
North  Pole. 


The  Sperry  Gyro-Compass 

The  Sperry  Gyro-Compass,  which  is  not  a 
Magnetic  Compass,  and  is  not  affected  by 
a  magnetism  of  any  sort,  and  derives  its 
directive  force  from  the  earth's  rotation, 
points  True  North.  It  does  not  point  to  the 
Magnetic  North  Pole. 


-"^n"*  ■■*•'■■ 'I' 


12 


^oo3pocrmrnrt 


The  S perry  ff 


^;fCn■-.-l^-^.■T■^^-.T^.^^\-tl>■r 


Gyro-Compass 


r-'^r>-^-,^>>-r-y^v>T,^-y^'^^<. 


A  (lalleiin.  the  trriksur'-  sliip  of  the  Spiiiil^h  M;iin 


Freedom  From 

Every  time  a  ship's  course  is  laid  or 
changed,  or  its  position  noted,  the  navigator 
must  make  and  apply  calculations  to  correct 
the  errors  caused  by  variation  of  the  earth's 
magnetic  fields,  and  deviation  due  to  local 
conditions  about  the  ship.  Mistakes  are 
frequently  made  in  applying  the  correction 
factors  by  applying  them  to  the  wrong  side. 
An  error  is  thus  introduced,  which  in 
magnitude  is  twice  the  correction  factor. 
Instances  are  reported  of  ships  being  200 
miles  out  of  their  courses  as  a  result. 


Calculation 


The  Gyro-Compass  requires  no  corrections 
since  it  is  undisturbed  by  variations  or  any 
local  magnetic  conditions.  The  reading 
indicated  by  the  Sperry  Gyro-Compass  is 
not  approximate — it  is  absolutely  and  im- 
mediately correct.  It  is  not  necessary  to 
correct  the  course  every  few  hours  for  vari- 
ation— the  navigator  is  freed  from  the  neces- 
sity of  making  calculations. 


.;  oa, 


Freedom  From 

After  the  navigator  has  made  calculations 
for  the  deviation  errors  of  the  Magnetic 
Compass,  they  must  be  applied  by  means  of 
manipulating  the  soft  iron  globes  and  com- 
pensating magnets.  This  is  an  operation 
requiring  such  a  high  degree  of  skill  that  only 
trained  men  calle<l  Compass  Adjusters  are 
qualified   for  the  work. 


Compensation 

The  occasional  turning  of  a  thumb  nut  is 
the  only  compensation  necessary  in  the  use 
of  a  Sperry  Gyro-Compass.  No  tables  or 
curves  are  required.  The  ship's  Navigating 
Officer  makes  this  adjustment  with  ease. 


13 


rk-f;iL'Y^-c,«,«SrtfyyP 


Of  RO-COMPASS 


Vl^^^^lT^  '■■■■■  ■■■-ntwt^t^twcvt^ 


Freedom  From 

Each  time  a  compass  is  compensated  it  is 
necessary  to  check  the  compensation  by 
checking  the  deviation  on  various  headings. 
This  may  be  done  by  the  use  of  deflector 
magnets.  A  more  exact  method  is  to  swing 
the  ship  in  a  circle  while  bearings  are  taken 
of  a  known  object  on  land  and  the  deviation 
noted  on  various  headings.  The  sun  is  often 
taken  as  a  reference  point  for  this  purpose. 


Checking  Deviation 

It  is  never  necessary  to  swing  ship  or  to 
correct  the  Gyro-Compass  for  either  varia- 
tion or  deviation  of  any  kind.  Where  a 
Gyro-Compass  and  a  magnetic  compass  are 
both  used  on  a  ship,  the  ship  may  be  swung 
to  correct  the  magnetic  compass — the  Gyro- 
Compass  furnishing  true  headings.  The 
time  required  is  thereby  materially  shortened. 


Influences  Due  to 

When  a  steel  ship  is  building  a  sub- 
permanent  magnetism  is  induced  in  its  keel, 
hull,  and  plates.  It  causes  a  compass 
deviation  classed  as  "semi-circular."  This 
deviation  must  be  compensated  for. 

As  a  ship  moves  through  the  earth's 
magnetic  fields  in  its  varying  quantities  and 
directions,  a  temporary  and  varying  mag- 
netism is  induced  in  the  soft  iron  of  the  ship. 
The  resultant  deviation  is  classed  as  "quad- 
rantal,"  and  must  be  compensated  for. 


Magnetism  of  the  Ship 

The  Sperry  is  not  a  Magnetic  Compass. 
Hammering,  riveting,  and  moving  through 
magnetic  fields  may  induce  magnetism  in 
the  ship,  but  will  have  no  effect  upon  the 
Sperry  Gyro-Compass. 

There  is  no  condition  of  the  ship  or  cargo 
for  which  the  Gyro-Compass  must  be  cor- 
rected. 


m^TTrrrrgvcrfsyic 


.*ijir,«jim'ifc»rctTnxi 


14 


The  S perry 


Gyro-Compass 


::5W 


^.^^fj-^fn^^j-f^-KfyiP 


An  American  Clipper,  liinliest  lypc  of  sailing  ships 


Influences  Due  to  Cargo 


Change  in  the  character  or  disposition  of 
the  cargo  of  the  ship  causes  a  change  in  the 
magnetic  fields  surrounding  the  compass. 
These  changes  must  be  compensated  for. 


The  Sperry  Gyro-Compass  is  not  affected 
by  any  cargo.     A  cargo  of  iron  ore  has  no. 
more  effect  upon  it  than  a  cargo  of  cotton. 
You  could  even  carry  a  load  of  strong  mag- 
nets without  causing  the  slightest  deviation. 


Influences  Due  to  Temperature  Changes 


Changes  in  the  temperature  of  the  stack, 
due  to  shifting  of  the  wind  and  force  of 
draft,  vary  its  magnetic  characteristics. 
Consequently  the  Magnetic  Compass  is 
affected. 


Temperature  changes  do  not  influence 
the  Sperry  Gyro-Compass. 

No  matter  what  the  conditions  are  that 
change  the  magnetic  characteristics  of  the 
stack,  ship  or  cargo,  they  cannot  affect  the 
Gyro-Compass,  as  it  has  nothing  whatever 
to  do  with  magnetism. 


■-'■'^'■^"'"  ^-.^^^^'-^ 


15 


The  S perry 


GfRO-COMPASS 


■  .  .  ,  f  .-«^^f  ......  ^.  .  .>^v>^->^r^ 


Fulton's  Clermont  nslicred  in  tlic  uge  of  Bteam 


Influences  Due  to  Roll  and  Pitch  of  the  Ship 


The  Magnetic  Compass 

Another  error,  called  heeling  error,  is 
caused  by  the  change  in  the  disposition  of 
the  material  of  the  ship  with  reference  to  the 
compass.  It  is  brought  about  when  the  ship 
rolls.  For  example,  a  ship  heading  on  a 
northerly  course  would,  if  rolled  to  port, 
place  all  magnetic  material  of  the  ship  to  the 
eastward  of  the  compass.  This  pulls  the 
north  end  of  the  compass  to  the  eastward. 
The  action  and  effect  would  be  just  opposite 
to  this  on  a  roll  to  the  starboard.  The  result 
is  that  the  needle  is  caused  to  oscillate  in 
either  direction.  The  helmsman  in  his 
attempt  to  keep  "on"  will  cause  the  ship  to 
traverse  a  sinuous  course. 

The  card  and  needle  of  the  magnetic 
compass  are  placed  in  a  bowl  filled  with 
a  liquid.  The  purpose  in  so  doing  is  to  make 
the  action  of  the  card  somewhat  sluggish,  so 
that  it  will  not  follow  very  slight  magnetic 
distractions  or  ship  movements.  Every 
time  the  course  of  the  ship  is  changed  the 
sluggish  action,  due  to  adhesion  between  the 
bowl,  liquid  and  card,  pulls  the  compass  off 
the  meridian.  Official  test  has  shown  that 
from  three  to  four  minutes  are  required  for 
the  compass  to  overcome  this  "  lag."  The 
"  lag "  is  somewhat  less  in  the  dry  card 
compass. 


The  Sperry  Gyro-Compass 

Not  only  is  the  Sperry  Gyro-Compass 
unaffected  by  magnetic  conditions,  resulting 
from  the  heeling  eiTor,  but  before  being 
placed  upon  the  ship  it  is  tested  for  days 
under  conditions  simulating  the  motion  of 
the  ship  in  the  most  severe  storm. 

A  ship  steered  by  the  Gyro-Compass 
traverses  a  straight  line  course;  the  Gyro- 
Compass  does  not  oscillate  with  the  rolling 
of  the  ship.  It  is  not  necessary  for  the  helms- 
man to  use  as  much  helm  to  keep  the  ship 
on  her  course.  A  great  saving  is  made  in  the 
use  of  the  steering  engine. 

There  is  no  "lag"  in  the  Sperry  Gyro- 
Compass,  because  it  does  not  leave  the 
meridian,  no  matter  which  way  or  how 
quickly  the  ship  may  turn  or  zig-zag.  Ex- 
haustive tests  have  been  conducted  on  com- 
passes installed  on  torpedo  boat  destroy- 
ers. Even  when  zig-zagging  at  top  speed 
in  heavy  seas  the  Gyro-Compass  shows  no 
"lag." 

Traveling  the  straight  line  course  instead 
of  the  sinuous  course,  ships  equipped  with 
the  Sperry  Gyro-Compass  have  saved  from 
one  to  ten  per  cent  in  time  over  the  aver- 
age schedule  time  required  to  cover  their 
courses  when  steering  by  the  magnetic 
compass. 


16 


1^ 


'  ''  .,,v 


r 


The  S perry 


^---^'^-"^^''r''-*'''*^^'''''*^'*^  <:i  inorTr-c 


GfRO-COMPASS 


r't>-'''^''1  VTl-''""^^!'' 


TheSkTConab.fintateuiiliiptoaaMtiieaeeu 


Due  to  magnetic  storms  and  any  number 
of  other  causes  the  magnetic  compass  may 
at  any  time  be  distracted  so  that  it  does  not 
indicate  correctly.  Disturbances  are  ex- 
traneous and  their  direction  and  magnitude 
cannot  be  determined.  The  navigator  is 
constantly  subject  to  the  feeling  that  his 
compass  may  not  be  accurate  —  that  he 
cannot  depend  on  it. 


Warning  of  Unreliability 

About  the  only  thing  that  will  cause  an 
error  in  the  Gyro-Compass  is  the  failure  of 
the  electrical  power  supply.  Should  this 
contingency  occur  an  electric  bell  warns 
the  navigator.  Any  disturbances  must  orig- 
inate with  the  master  compass  and  can  be 
quickly  and  accurately  located. 


The  Sperry  Gyro-Compass  unfailingly  points  True  North  under  all  conditions  of 
weather,  ship  or  cargo.  It  relieves  the  navigator  of  calculation  of  errors,  and  tiresome 
compass  compensations.  It  makes  a  great  saving  in  time  required  to  "swing  ship." 
The  Sperry  Gyro-Compass  is,  therefore,  the  Ideal  Compass. 


acBQOODDQCEACa 


17 


The  S perry 


r=° 


GfRO-COMPASS 


xfaaoaxfaBGOccaaacsocQQCC 


The  Great  Eastern  laid  the  first  Atlantic  cable 


Advantages  Attending  the  Use  of  the  Sperry  Gyro-Compass 

fURiNG  the  construction  of  a  steel  ship  it  is  usual  to  build  it  on  ways  the 
direction  of  which  lie  in  the  East- West  line.  Should  the  ways  be 
placed  in  a  North-South  line  the  riveting  on  the  keel  and  plates  tends 
to  help  the  molecules  of  metal  to  place  themselves  parallel  to  the 
magnetic  lines  of  force,  and  magnetize  the  metal.  When  placed  in 
the  East- West  line  the  molecules  of  metal  in  the  plates  are  at  right 
angles  to  the  magnetic  lines  of  force,  and  are  not  as  easily  mag- 
netized. The  use  of  the  Gyro-Compass  eliminates  the  necessity  of  placing  the  ways 
in  the  East-West  line. 

After  a  large  ship  has  been  launched,  and  during  the  fitting  out  period,  it  is  often 
necessary  to  have  it  swung  end  for  end  in  order  to  neutralize  or  equalize  the  magnetism 
induced  by  the  earth's  magnetic  field.  To  swing  a  large  ship  end  for  end  costs  anywhere 
from  one  thousand  ($1000)  to  three  thousand  ($3000)  dollars.  The  Gyro-Compass  is 
unaffected  by  any  magnetic  phenomena,  and  is  so  dependable  that  it  makes  the  swinging 
of  the  ship  unnecessary. 

In  constructing  a  ship  it  is  customary  to  make  all  metal  parts  within  approximately 
ten  (10)  feet  of  the  magnetic-compass  stand  of  bronze,  brass  or  other  non-magnetic 
material.  The  proximity  of  magnetic  metals  seriously  affects  the  accuracy  of  the  com- 
pass. All  electric  leads  are  run  so  as  to  clear  the  vicinity  of  the  compass,  as  the  magnetic 
fields  set  up  by  such  conductors  seriously  influence  the  compass  needle.  Actual  experi- 
ence is  on  record  that  the  total  installation  cost  of  the  Sperry  Gyro-Compass  has  been 
saved  many  times  over  by  the  elimination  of  special  metals  and  special  run  of  electric  leads. 
Before  starting  on  a  long  voyage,  especially  with  a  new  ship  using  the  magnetic 
compass,  it  is  customary  to  swing  the  ship  through  a  complete  circle  to  check 
deviation.  To  swing  ship  it  is  first  necessary  to  pick  out  a  suitable  object  on  land 
having  a  known  bearing  to   the  ship.      This   object  is  used  as  a   reference  point. 

If  at  sea  observations  are  taken  on 

H^  ^  ^^^H^^^^^^^^^^^^^K^  i  ^^m       ^^^  ^^^'     ^^^  ^^^^  ^^  ^^^^  swung 

■  ""'^  ^^^^^^^^^^^^^^K^  ^^H       through    360     degrees,     stopping 

P  ^s^^K/f^^^^^^^^K^Mm  ^^H       usually  on  each  15-degree  heading, 

and  noting  the  deviation.  A  table 
is  made  up  showing  the  deviation 
on  each  of  these  headings.  An 
attempt  is  then  made  to  so  adjust 
or  manipulate  the  compensating 
magnets  to  eliminate  the  error 
found.  The  ship  must  then  again 
be  swung  through  360  degrees, 
stopping  at  headings  as  before  to 
check  the  applied  compensation. 

Ciyro-Coiripass  SIkriI  for 
Training  Ship's  Ofliofrs  and  Men 


18 


Ycri-ftYfTrffvmri  i  ^vmiftMi 


The  S perry 


GrTRO-COMPASS^ 


rrremoi-nnuinuTj 


A  Stern-wheeler  of  early  steam-boating  daya 


On  some  ships  it  is  the  custom  to  check  the  deviation  by  the  deflector  magnet 
method.  The  ship  in  this  case  is  put  on  a  certain  heading  and  a  magnet  placed  to  one 
side  of  the  compass  and  the  deviation  noted.  The  same  magnet  is  then  placed  at  an 
equal  distance  to  the  opposite  side  and  the  deviation  noted.  The  difference,  if  any, 
between  the  readings  is  the  deviation  on  that  particular  course. 

With  either  method  of  checking  for  deviation,  considerable  time  is  used.    It  is  not 

necessary  to  check  for  deviation  or  apply  any  compensation  to  the  Gyro-Compass,  as  it 

is  not  magnetic.     In  fact  the  Gyro-Compass  has  nothing  whatever  to  do  with  magnetism. 

When  at  sea  the  Gyro-Compass  affords  the  means  of  keeping  to  the  straight-Une, 

true  course.     The  Hne  A  B,  Figure  5,  shows  the  straight-Une  course  from  the  port 

of  New  York  to  the  port  of 
Liverpool.  The  line  A  C  E  B  shows, 
with  exaggeration,  the  actual 
course  steered  due  to  compass  and 
other  errors.  At  the  point  E  the 
ship's  position  was  checked  by 
observation  of  a  celestial  body. 
The  line  E  B  represents  the  new 
course  set  to  bring  the  ship  to  her 
destination.  This  is  an  occurrence 
which  sometimes  happens  not  once 
but  often  during  a  voyage. 

Errors  of  Magnetic  Compass  Cau^D^parture  From  Desired  Course  ,      .  ^^  *f  evident  that  a  loSS  of  time 

is  mvolved  when  the  ship  leaves 
her  straight  line  course.  The  inherent  accuracy  of  the  Sperry  Gyro-Compass  enables 
the  ship  to  keep  to  the  straight  line  course,  and  also  to  steer  directly  on  true  courses. 

By  keeping  on  a  straight  line  course  the  ship  is  enabled  to  make  a  good  many  more 
miles  on  the  same  number  of  revolutions  or  turns  of  the  propeller.  Under  exactly  the 
same  weather  conditions  a  16,000 
ton  Hner  made  370  miles  in  24 
hours  at  an  average  of  86.95 
revolutions  per  minute  per  mile 
when  steered  by  a  magnetic 
compass,  and  the  same  liner  made 
377  miles  with  85.61  revolutions 
per  minute  per  mile  when  steered 
by  the  Gyro-Compass.  This  sav- 
ing amounts  to  easily  $50  per  day 
for  this  ship.  During  her  eleven- 
day  voyage  she  saved  $550.  At 
this  rate  of  saving  the  Gyro-Com- 
pass equipment  is  soon  paid  for. 

XciTiiiif  Hc|)<>at«:r 
in  W  luM-l  Hoiisi- 


19 


.■XitccijL:.i.s.s:i 


The  S perry 


GfRO-COMPASS 


PtTTv^^^MlT^^'^^'T^'l^''^''"^ 


The  Turbinia  was  the  first  turbine  steam  er 


The  Sperry  Gyro-Compass  does  not  oscillate  with  the  rolling  of  the  ship,  or  in 
other  words,  has  no  heeling  error.  The  use  of  the  helm  is  greatly  diminished .  Records 
show  that  on  one  trans- Atlantic  liner  a  saving  of  24  percent  in  the  revolutions  of  the 
steering  engine,  when  steered  by  Gyro-Compass,  was  effected.  One  of  the  largest 
trans-Atlantic  liners  reports  that  but  one-third  of  the  helm  is  used  when  the  ship  is 
steered  by  Gyro-Compass. 

This  saving  in  the  use  of  the  steering  engine  gives  actual  proof  that  the  ship  navigated 
by  a  Gyro-Compass  steers  a  straight  line  course.  It  further  proves  that  the  ship  does  not 
divert  its  slip-stream  as  often — the  power  output  of  the  main  engines  is  thereby  reduced. 

Records  taken  on  a  well-known  passenger  liner  show  that  in  making  her  regular 
trip  between  New  York  and  Jacksonville,  Florida,  she  saved  more  than  two  hours 
due  to  steering  by  a  Sperry  Gyro-Compass.  A  saving  of  3,410  turns  of  her  propeller 
was  also  effected.    These  savings  were  made  even  with  much  greater  than  the  usual  draft. 

Records  taken  by  means  of  the  Sperry  Recording  Compass  show  that  when  the 
helmsman  is  given  a  certain  course  he  can  keep  the  ship  one  and  one-half  degrees 
nearer  the  course  when  steering  by  the  Gyro-Compass  than  when  steering  by  magnetic 
compass. 

The  Gyro-Compass  can  make  great  savings  in  money  both  in  construction  and 
operation  of  the  ship.  These  factors  are  perhaps  trivial  when  compared  with  the  safety 
factor  introduced  by  the  use  of  the  Sperry  Gyro-Compass. 

Due  to  the  elimination  of  the  many  uncer- 

P,^^^^^  tainties  of  the  magnetic  compass,  insurance  com- 
1  _9i|^H  panics  are  favorably  disposed  toward  the  use  of 
'  ^^Hl        the  Sperry  Gyro-Compass,  which  ultimately  will 

I       '*    ^^M        result  in  a  reduction  of  insurance  rates. 
I  r^!^-s  s-  ^  The  use  of  the  Sperry  Gyro-Compass  elirai- 

I  {'-.atmlttK^^        nates  inaccuracies   due    to  navigation,   thereby 

PH  I  saving  time,  insuring  the  ship,  the  cargo,  and  the 

^  /  lives  of  passengers  and  crew. 

~\  f  Sperry   Gyro-Compasses    are    operating   on 

many  of  the  world's  largest  and  fastest  passenger 
liners  and  cargo  ships.  These  ships  are  making 
savings  every  day  of  fuel  used  and  time  required 
to  make  their  courses.  The  navigators  using 
these  compasses  find  that  they  can  come  very 
much  nearer  their  calculated  positions  when 
steering  by  the  Gyro-Compass.  The  Gyro- 
Compass  makes  the  art  of  navigation  more  exact. 
The  Sperry  Gyro-Compass  is  the  only  one  to 
pass  the  service  tests  in  the  world's  navies. 

,    I'oti-iiiNir  Ti'si 

M  lli'|»fnt<*rs 


nirtrirriirTrrrr-iTrrn — 


YT^-.'^-.^^'f^-^'v^'^f'^f^' 


20 


The  S perry 


G^RO-COMPASS 


-^'rP''"^  ^-"fTTP'^''^^^  rtr^^actt  ^  jJc^-^tc 


Sflhmnerfi  arr  <.vuik>iiiK'u!.  neoiniK  l>iit  ^luull  t.TeM 


The  Sperry  Gyro-Compass  Equipment 

HE  equipment  which  apphes  the  principle  set  forth  in  a  practical  way 
consists  of: 


1. 
3. 

2. 


5. 


The  Master,  True  North  Compass. 

Compass  Control-Panel — for  controlling  the  electric  current. 
Repeaters — operated  from  the  Master  Compass,  and  indicat- 
ing its  exact  reading  at  any  instant. 

Motor-generator — for  converting  the  ship's  current  into  cur- 
rent of  proper  characteristics  for  spinning  the  gyro  wheels  and 
operating  the  repeaters. 

Storage  Battery  —  for  emergency  operation  of  the  equipment 
in  case  of  failure  of  the  ship's  supply. 


The  function  of  each  piece  of  equipment  and  its  relation  to  other  parts  is  shown 
on  pages  22  and  23. 

The  Master  Compass 

The  Master  Gyro-Compass  is  contained  within  a  binnacle  stand,  with  glass  dome  top. 

As  shown  in  the  photographs  and  sectional  view,  the  twin  gyro-wheels  are  supported 
from  a  frame-work  which  is  in  turn  set  in  gimbal  rings.  The  outer  gimbal  ring  is  at- 
tached to  the  binnacle  stand  by  means  of  a  number  of  supporting  springs .  The  springs 
are  provided  for  protecting  the  compass  against  sudden  jars  and  vibrations.  Figure  18 
shows  a  photograph  of  the  top  view,  while  the  wheels  are  shown  from  below  in  Figure  16. 

A  diagrammatic  representation  of  the  Sperry  Gyro-Compass  is  shown  in  plan  view 
in  Figure  17.  The  elevation,  or  side  view,  is  shown  in  Figure  15.  These  drawings 
show  the  working  parts  of  the  Gyro-Compass.  Each  of  the  twin  gyro-wheels  is 
enclosed  in  a  case,  which  is  in   turn  suspended  from   the  main  frame  and  spider. 

The  wheels  are  spun  at  a  high 
speed  in  unison  by  means  of  elec- 
tricity. The  force  of  the  earth's 
rotation  combines  with  the  force 
resulting  from  the  rotating  wheels. 
The  resultant  action  of  these  two 
forces  is  that  both  wheels  turn  their 
axes  directly  into,  or  parallel  with, 
the  earth's  north  and  south  meridian. 
The  compass  card,  of  course,  also 
turns  and  indicates  direction  by  com- 
paring the  stationary  "lubber  line," 
representing  the  ship's  head,  with 
the  compass  card. 


21 


Gyro-Compass 


Hep«iator  on  Slwrint;  St^iiid 
»^^■7V'^■^^.^^^i■'■^<^vrgTT^^  i  tctttoss 


■C-?CT-TOCtXir-rfC.»^<-c«t.tt^t'^«.i^~rf-f.-.>r.p,-^yyt>.,.,<,<s,^^ 


23 


The  S perry     =. 


-'^g^"^'^^'^^^^ft^'t~'''''"^^'^''~^'^'^'^~''v-^-^'-^-^^--y.r 


The  Dhow  ig  the  txading  ship  of  East  AMoa 


A  single  gyro-wheel  would  constitute  a  satisfactory 
stationary,  or  "land  compass."  On  shipboard  the  roll, 
yaw  and  pitch  of  the  ship  would  impose  additional  duty 
on  a  single  wheel.  It  would  have  to  point  not  only  True 
North,  but  also  offset  the  effect  of  the  sea.  One  of  the 
two  wheels  is  arranged  to  always  point  True  North, 
while  its  twin  wheel  opposes  and  neutralizes  all  influences 
other  than  the  force  of  the  earth's  rotation.  The  force 
of  both  wheels  is  utilized  in  seeking  the  meridian. 

The  Master  Gyro-Compass  is  a  marvel  of  mechanical 
perfection  and  ruggedness.  Every  rotating  or  revolving 
part  moves  upon  special  bearings  to  reduce  friction.  It 
should  be  noted  also  that  the  gyro-wheels  do  not  directly 
operate  the  compass  card.  The  compass  card  is  turned 
by  a  small  electric  motor  (Azimuth  Motor),  Figure  17. 
The  slightest  change  in  position  between  the  wheels  and 
card  operates  the  "trolley"  or  electrical  contact,  which 
controls  the  Azimuth  Motor.  The  card  is  made  to 
"shadow"  the  wheels.  The  follow-up  is  so  close  that  the 
card  frame  has  been  called  the  "phantom." 

An  electrical  transmitter.  Figure  17,  is  operated  by 
the  movement  of  the  card.  This  transmitter  is  the  means  by  which  the  repeaters  are 
kept  in  unison  with  the  movements  of  the  Master  Gyro-Compass,  and  made  to  show  the 
exact  reading  at  any  instant.  Again  the  Azimuth  Motor  furnishes  the  very  slight 
amount  of  power  required  to  operate  this  device. 


Fiffure  11 


Figure  13 

The  Master  Compass  is  placed  near  the  center  of  the  ship  at  the  water  line.  At 
this  point  the  effect  of  rolling  is  at  a  minimum.  It  is,  however,  not  necessary  to  place  it 
exactly  at  this  position.  Figure  13  shows  the  approximate  location  of  the  various 
pieces  of  equipment  aboard  ship. 

The  Repeaters 

A  familiar  application  of  the  repeater  principle  is  that  used  in  hotels  and  public 
buildings,  where  a  number  of  repeater  clocks  are  operated  from  one  master  instrument. 
Likewise,  the  repeater  used  upon  the  bridge,  the  bearing  repeater,  and  the  one  at  the 
after  steering  station,  are  all  operated  by  electricity  in  perfect  unison  with  the  Master 


24 


JtaBtttftaccMcfirre 


The  S perry 


GfRO-COMPASS 


An  indispeiisable  link  between  prudutM-r  mid  i-uiisiimt-r 

Gyro-Compass  and  show  the  exact  reading  of  the  Master  at  any  instant.  Repeaters  are 
operated  by  a  small  electric  motor  within  each  case,  controlled  by  the  transmitter  at  the 
Master  Gyro.  In  designing  the  repeaters  particular  attention  has  been  given  to  the 
electrical  circuits  so  as  to  make  all  connections  water,  spray  and  condensation  proof. 
Stuffing  tubes  of  improved  design  are  used  at  all  outlets  and  entrances. 

A  miniature  electric  lamp  within  the  repeater  supplies  the  necessary  illumination 
of  the  dial.  The  illumination  can  be  brightened  or  dimmed  by  turning  the  switch  handle 
on  the  face  of  the  terminal  box. 

The  repeaters  are  supplied  in  three  styles : 

1.  Repeater  mounted  on  steering  stand — for  use  on  bridge. 

2.  Bearing  repeater  mounted  within  pelorus  stand. 

3.  Repeater  mounted  on  bulkhead  in  Master's  room,  or  at  the  after  steering  station. 

Special  stands  or  fixtures  can  be  supplied  if  necessary, 

A  metal  "non-reflection"  cover  is  supplied  which  can  be  fitted  to  either  the  bridge 
or  the  after  steering  repeaters.  The  cover  has  adjustable  doors  and  a  hood.  Its  object 
is  to  exclude  all  light  from  the  top  glass  of  the  repeater  except  at  the  lubber's  line.  No 
light  will  be  reflected  into  the  eyes  of  the  helmsman.  The  doors  can  be  closed  until  a 
very  small  sector  of  the  repeater  dial  appears  at  the  lubber's  line.  Experience  has 
proved  that  it  is  easier  to  watch  and  concentrate  when  only  a  small  portion  of  the  dial 
is  visible.  A  magnifying  glass  can  be  used  in  conjunction  with  the  cover  so  that  the 
repeater  indication  can  be  read  at  a  distance. 

The  bridge  and  after  steering  repeaters  are 
mounted  on  adjustable  brackets.  The  position 
of  the  repeater  can  be  changed  so  as  to  allow  a 
full  face  view  of  the  dial  from  almost  any  angle. 

The  bearing  repeater  is  of  great  aid  to  the 
navigator.  The  repeater  is  mounted  within  the 
stand  and,  of  course,  shows  the  exact  reading  of 
the  Master  Compass.  In  taking  a  bearing  on  a 
distant  object  or  a  sun  azinuith  it  is  not  necessary 
to  first  set  the  "dumb"  compass  to  correspond 
with  the  main  compass.  A  constant  true  indica- 
tion is  afforded. 

Installation  of  the  bearing  repeater  can  be 
made  in  such  a  position  on  the  upper  bridge  so 
that  it  may  be  used  for  steering  from  that 
position  as  well  as  for  taking  bearings.  A  special 
pelorus  stand  cover  can  be  supplied  w  ith  w  indow  s 
to  allow  steering  with  the  cover  on,  so  as  to  pro- 
tect the  repeater  from  spray  and  the  weather. 

Bt'iiciiijr  I<c[>riitcr  v 
S|H'rr\    V/.iiiiutli 
Cin 


25 


?•*';■!•'; 


^sacccgcccncBcacnxoccocctMasc 


The  S perry 


QfRO-COMPASS' 


'T'~^Tv"'"^''T''^''''''"""''^'^''^^'''^^'''^''*'*^ 


^^ 


The  U^t  uoflinkable  Kayak  of  the  Eskimo 


TmE     TsWO    \>yMEELS    NWMICn    COMBiNe 

Tneia  Action  In  Seeking  TtiE  necioiAN 
But  Neutcal^ze  In  Each  Otmee  Any 
Effect   Which   Tme   Smip's  D.olung 

And    Pitching    Mav    CauSE 


Tme    Beadings    On 
WmcM    The  Wheels   Dotate 


Figure  15 


Figure  16 


r-^'^""'"  ■■  V  ^  »  ■.  1  Tincet- 


26 


/^$\     The  S perry 


3jSS> 


Qtro-Compass  (i 


An  (_>re-8t*aii)er  of  the  American  Great  Lakes 


Figure  17 


Figure  18 


27 


The  S perry 


inffgyflcgficcga: 


G^'RO-COMPASS 


The  great  painted  War-Canoe  of  Alaskan  Indians 

An  improved  design  of  azimuth  circle  is  furnished  which  fits  directly  over  the  top 
of  the  repeater.  Figures  24  and  26,  on  page  30,  show  the  azimuth  circle  and  bearing  re- 
peater in  use,  taking  a  bearing  on  a  distant  object,  and  on  the  sun  respectively.  This 
azimuth  circle  is  so  constructed  as  to  bring  the  object,  the  spirit  level  and  dial  within 
the  field  of  vision  concurrently.  The  bearing  can  be  taken  with  great  accuracy.  There 
is  no  possibility  of  the  Master  Compass  changing  its  position  while  the  pelorus  is  in  use. 
Such  an  occurrence  is  not  uncommon  when  using  the  ordinary  pelorus  or  "dummy  "compass. 

An  additional  graduated  ring,  Figure  25,  is  supplied  for  placing  under  the  azimuth 
circle  so  that  in  case  the  Gyro-Compass  is  not  operating  such,  for  instance,  as  when 
the  ship  is  at  anchor,  the  pelorus  can  still  be  used  as  a  "dumb"  compass.  The  main 
compass  setting  is  made  upon  the  ring,  and  the  azimuth  circle  used  in  the  usual  manner. 

The  bearing  repeater  can  be  furnished  with  any  one  of  three  kinds  of  azimuth 
circles.  The  Ritchie  circle  is  usually  supplied.  The  purchaser  also  has  the  option  of 
choosing  either  the  Sperry  circle  or  the  Kelvin  Azimuth  Mirror. 

Compass  Control-Panel 

The  compass  control-panel  provides  a  means  for  controlling  the  various  electrical 
parts  of  the  Gyro-Compass,  the  storage  battery,  motor-generator  and  ship's  supply 
current.  It  is  very  compact,  neat,  and  of  good  appearance.  It  receives  electrical  power 
from  the  ship's  mains  and  distributes  it  to  the  motor-generator  set.  Master  Compass 
and  repeater. 

The  switch  panel  is  made  up  of  black  ebony  asbestos,  mounted  upon  angle  iron. 
The  panel  is  usually  mounted  with  its  back  near  the  bulkheads,  but  so  hinged  as  to 
admit  of  access  to  its  rear. 

Motor-Generator 

The  Motor-Generator  supplied  is  an  efficient  and  exceptionally  reliable  piece  of 

equipment.  Its  purpose  is 
to  convert  the  ship's  supply 
current  into  electricity  of  the 
characteristics  used  in  spin- 
ning the  gyro-wheels  and 
operating  the  repeaters. 

Storage  Battery 

The  complete  failure  of 
the  electrical  plant  aboard  a 
modern  ship  is  an  event  of 
rare  occurrence.  If,  how- 
ever, such  a  contingency 
should   occur,  provision  has 


Trrrf' MM'i"'^ 


ri'rfirr'-"t''*i"'""''^^'"''*'''^' 


Bac$°: 


etrtfu'iiiiim. 


28 


im^^ 


The  S perry 


GYROCOMPASS 


-  -rcna 


A  t^uptir-drt-aJiiuuKliI..  llif  Ijuluark  vi  M-a  |>uwff 


GfRO-COMPASS      fi 


■-^•^y.     -■-■^r-^.r»>->^>-^-Y^Yr— ^T^7—    fV 


The  S perry 


r^firg^-^^'^nf''-'''^'''"  ■"•'■■--^-■^•^"-"-<^«^»-<''*t*-*'W'^ 


ii  i.icn--.  ^ijtii.i 


.  :i^L-  rry<-rvjtV^c-.-i-rt-r» 


XCOOCOCQCCGCC 


The  S perry 


''«^*-^  •^^''^^'^'^-T''X^^fflTfrT<^^TTrrv^^Tr^r^^^ 


^      G^RO-COMPASS 


ci.'oaixvypcfcrfctTjCi.ri 


Malay  pirates  use  the  swift-sailing  l*r(i:i 


-*.s^;^^> 


Figure  31 


been  made  for  it  in  the  Gyro-Compass  equipment  by 
supplying  a  storage  battery  of  sufficient  capacity  to 
operate  the  entire  equipment  for  a  period  of  two  hours. 
The  battery  is  so  connected  electrically  as  to  keep 
itself  in  a  charged  condition  while  the  compass  is 
operating  under  normal  conditions. 

Sperry  Recording  Compass 

An  outstanding  feature  of  the  Gyro-Compass  is 
that  it  makes  possible  the  recording  of  the  actual 
courses  steered  by  a  vessel.  The  recording  compass 
is  connected  to  the  electrical  circuits  like  a  repeater 
and  follows  the  movements  of  the  Master  Compass. 
It  not  only  indicates  the  heading  at  any  instant,  but 
also  makes  a  graphic  record  on  a  chart.  Radial  lines 
on  the  chart  represent  the  various  courses.  Concen- 
tric circles  represent  time — each  small  division  five 
minutes — each  large  division  one  hour. 

The  dial  on  which  the  chart  is  mounted  turns 
with  the  movements  of  the  master  compass  bringing 
the  correct  course  under  the  marking  point.     As  the 

time  advances  a  line  is  marked  on  the  chart  showing  the  exact  course  steered  at  a 

definite  time.     On  starting,  the  marking  arm  is  at  the  inner  edge,  clockwork  moves 

it  toward  the  outer  edge  with  uniform  motion. 

The  chart  shown  in  Figure  32  forms  a  valuable  record.    It  was  taken  on  a  ship  at 

a  time  a  radio  call  was  received  from  a  burn- 
ing oil  tanker.    Being  within  the  distance 

defined  by  law,  the  ship  was  legally,  as  well 

as  morally  bound  to  proceed  to  the  dis- 
tressed ship.     The  chart  shows  that  the 

course  was  altered  to  go  to  the  tanker's  aid. 

It   also    showed    the   exact  time,  thereby 

establishing  proof  as  to  the  fulfillment  of 

the  obligation.    A  few  minutes  later  another 

radio  call  advised  that  the  fire  aboard  the 

tanker  was  extinguished.    The  chart  shows 

that  the  course  was  again  altered  to  bring 

the  vessel  back  on  her  original  given  course. 
The   chart   further   shows  the   actual 

courses  steered  in  holding  the  ship  on  its 

Figure  32 


^-^ 


••».T.?-> 


X 


^ttOSSCO 


rtyrqrcct'PKWCayiaag 


f'^-'tv^'fTrir.-TrT-i.-vry--' 


"'-  N-^->r^r^-yx-c-t-t-irr\r-tvyvv-:ffV\-r 


32 


The  S perry 


.  tMi^HaJAiJS^ 


Gyro-Compass 


iiMiii>iVmiii>i- 


The  Deatroyer  a  the  (njr-houiid  of  tiw  an 


given  course.  It  shows  just  how  efficiently  each  helmsman  handles  the  ship.  It  provides 
an  excellent  method  of  training  helmsmen  to  use  less  helm,  effecting  a  saving  by  less 
frequent  use  of  the  steering  engine. 

The  recording  compass  is  a  great  aid  to  the  Captain  and  Navigator  in  improving 
the  navigating  efficiency  of  the  ship. 

The  recording  compass  can  be  supplied  as  a  part  of  the  Gyro-Compass  equipment — 
its  additional  cost  is  small  when  compared  to  the  saving  and  benefits  derived  from  its  use. 

Operation 

The  operation  of  the  Sperry  Gyro-Compass  is  made  easy  by  making  all  parts  as 
simple  as  possible. 

In  starting  the  equipment  it  is  necessary  to  turn  but  one  switch.  The  twin  wheels 
immediately  start  spinning  and  will  in  a  short  time  come  up  to  the  normal  speed. 

After  the  speed  has  been  attained,  a  short  time  is  allowed  for  the  wheels  to  cause 
their  axes  to  "settle,"  or,  in  other  words,  to  seek  and  hold  the  meridian. 

In  case  of  failure  of  the  ship's  supply,  or  other  trouble,  an  audible  signal  inunediately 
gives  indication  that  something  is  wrong.  This  is  a  decided  improvement  over  the 
ordinary  compass,  as  no  indication  is  afforded  of  the  presence  of  factors  which  cause 
errors  in  its  reading. 

Care 

All  of  the  greatest  commercial  aids  require  some  care,  such,  for  instance,  as  the 
telephone,  typewriter,  adding  machine,  duplicating  machine  and  so  on. 

The  magnetic  compasses  aboard  ship  re- 
ceive especially  watchful  attention,  to  see  that 
they  are  not  meddled  or  tampered  with.  As  a 
rule  the  entire  ship's  crew,  including  the 
youngest  apprentice,  knows  that  the  compass 
must  in  no  way  be  handled. 

It  should  be  remembered  that  the  Sperry 
Gyro-Compass  is  a  mechanical  compass.  Al- 
though the  very  best  materials,  design  and  skill 
enter  into  its  construction,  it  is  still  liable  to 
failure.  Even  with  that  possibility,  it  is  so 
superior  to  the  magnetic  compass  that  it  more 
than  justifies  its  installation  use.  In  the  same 
way  the  electric  light,  although  liable  to  failure, 
is  vastly  superior  to  the  old  oil  lamp.  The  oil 
lamps  are  seldom  used,  yet  they  are  carried 
aboard  ships  for  the  contingency  which  might 
happen.  Similarly  a  failure  of  the  electric  or 
hydraulic  steering  gear  may  necessitate  the 
temporary-  use  of  the  inefficient  hand-steering 
gear. 

I3eariii,  , 
liquipi"'!  witli  \^ 

il: 


33 


-.■r- ~  .-^^'i'r'<-<-fitirt^ri-^-^i'jtr'rx.^r^-€-<^-t^.-^-r^y^^ 


^gcnoccoocoocoQgafloafgMoooaKiaan 


The  S perry 


Of  RO-COMPASS 


cccoaaoirg. 


In  Venice,  graceful  Gondolas  take  the  place  of  cabs 


mywi.ocgta».Tinpr 


rr^^^t.^rr^^^,-^^,,,-.-..-cc^'r^^-ef^^^.-^r^^^  "  '  '  "'''  ^^'^^ 


34 


JSaXtX^KSU  1X»3JMOCt.tT>-^  --  J.^.:u. -^ 


The  S perry 


•5??> 


-^ 


GfRO-COMPASS 


mac-v  ;^.f.^wy).  %.Yii  fvy  r^rttr^ 


St«3uo-yaefaiiDg  is  the  most  coetly  of  all  sports 


N 


35 


iiaccococctn::^--  ~ 


The  Sperry  n  i 


aaccaogyiaaax 


GfRO-COMPASS 


The  Mediterranean  Felucca,  swift  in  all  weathers 


Maxtor 
Conipns>. 
on  Long  Run 
Floor  Test 


t'i^'.  a'.^      \lash-r 

rnpusw's    un<lt>r 

^p<x:inl  Ma<'hin<' 

1  <>ii.~lnict<.'<l  to  siiniJule  thi- 

(ion  of  ;i  Sliip  in  a  Heavy  Sfii 


36 


The  S perry 


Compass 


The  Sufamariiw,  the  unaen  toror  of  the  nu 


'**5«^^:^' ^tj; 


Sperry  Service 

iiKN  a  Gyro-Compass  is  sold  the  interest  of  The  Sperry  Gyroscope 
(>onipany  does  not  cease.  Our  interest  in  our  customer  is  only  begin- 
ning. An  experienced  service  engineer  installs  every  Sperry  Gyro- 
(^.onipass.  This  engineer  is  also  available  to  make  the  first  trip  with 
the  compass  in  order  to  assure  its  proper  operation.  After  instal- 
lation the  Sperry  Service  Engineers  are  available  in  every  large 
port  in  the  world  to  come  aboard  and  inspect,  clean,  repair  and  over- 
haul the  Gyro-Compass  equipment  so  as  to  keep  it  in  first  class  operating  condition. 
A  radiogram  sent  to  any  of  the  Sperry  Service  Stations  will  bring  a  Service  Engineer  to 
meet  your  ship.  During  the  first  year  there  is  no  charge.  After  this  period  a  reason- 
able charge  is  made  for  the  service.  Such  a  charge  is  similar  to  that  at  present  made 
by  compass-adjusters. 

A  list  of  the  Sperry  Representatives  is  given  on  the  title  page  of  this  book. 

Workmanship 

The  Sperry  Gyro-Compass  is  an  instrument  of  precision.    From  the  work  done  by 
the  Gyro-Compass  and  the  objects  accomplished  it  would  be  natural  to  class  it  as  a 
scientific  instrument.     It  is,  however,  more  than  that  for  the  reason  that  it  has  been 
made  strong  and  sturdy  for  operation  under  the 
most  severe  conditions  at  sea.    The  most  expert 
and  skilled  workmanship  is  required  to  combine 
strength   and  precision,   such   as  found   in   the 
Gyro-Compass.    The  Sperry  organization  prides 
itself  upon  having  the  best  workmen  that  can  be 
obtained  for  their  respective  vocations. 

The  materials  used  are  the  very  best  obtain- 
able. The  rigid  and  inflexible  set  of  purchasing 
specifications  insures  receiving  the  best  materials. 

A  well  organized  inspection  force  passes  upon 
all  material  upon  its  receipt,  and  through  the 
various  manufacturing  stages  to  the  final  product. 


Testing 

Each  Sperry  Gyro-Compass  is  on  test  for 
several  days.  During  this  time  it  is  put  through 
every  devisable  test  to  simulate  the  conditions 
under  which  it  will  have  to  operate.  Figures  38  and 
39  show  a  compass  mounted  on  a  stand  which  is 


ai 


4 


I   .■  (.11 1- 


37 


,^x&C£ccca^ 


aBQoccaoccnaccQOcoacflCQO 


The  S perry 


GfRO-COMPASS 


a'ny-^'^'i  ^^c^--^  -tt^^^^''^^*^^-^'*^^  ■■  ■ 


Hie  Sampan  shoots  the  rapids  of  Japanese  rivers 

operated  by  means  of  motor  driven  gears,  cams,  etc.,  so  as  to  reproduce  the  roll,  pitch 
and  yaw  of  a  ship  at  sea.  Absolute  accuracy  of  the  Master  Compass  and  all  repeaters 
while  operating  under  this  condition  is  required. 

The  purchaser  is  thereby  assured  that  the  compass  to  be  installed  upon  his  ship  will 
have  had  all  manufacturing  inaccuracies  or  so-called  "kinks"  worked  out.  A  record 
of  the  test  accompanies  each  compass. 

Packing 

Special  care  is  taken  in  packing  the  Gyro-Compass  for  shipment.  Experience 
gained  from  the  shipment  of  hundreds  of  compasses  has  devised  means  whereby  to 
insure  the  safe  arrival  of  all  parts  so  that  installation  will  not  be  delayed. 

In  order  that  no  injury  may  result  to  any  parts,  the  Gyro-Compass  is  unpacked 
under  the  supervision  of  the  Sperry  Service  Engineer. 

The  Sperry  Service  Organization 

The  Sperry  Service  Organization  is  one  which  serves  in  all  parts  of  the  world. 
A  corps  of  Service  Engineers,  having  special  training  at  the  factory  in  all  departments 
relating  to  the  Gyro-Compass,  are  available  in  nearly  every  large  port  of  the  world. 
These  engineers  are  ready  to  come  aboard  your  ship,  to  clean,  adjust  and  overhaul  the 
Gyro-Compass,  thus  relieving  the  navigator  of  all  care  other  than  the  actual  use  of 
the  Gyro-Compass. 

During  the  war  we  had  Service  Engineers  in  every  port  where  the  ships  of  the  Navy 
were  likely  to  call.  Our  men  have  been  in  many  of  the  naval  actions  and  have  been 
able  to  render  very  considerable  service  on  many  unusual  occasions.  For  example,  it 
was  desired  to  place  an  equipment  on  a  British  ship  which  was  on  her  way  to  the  Dar- 
danelles.   The  Admiralty  instructed  us  by  telegram  to  have  an  equipment  and  a  Service 

Engineer  meet  the  ship  at  the  British 
Naval  Station  at  Malta  in  the 
Mediterranean.  By  sending  the 
equipment  with  our  Service  Engineer 
via  a  passenger  train  to  the  south  of 
Italy  and  via  destroyer  to  Malta  we 
were  able  to  meet  the  ship  there  on 
the  day  she  arrived.  The  ship  was 
able  to  stay  only  twenty-four  hours, 
and  as  it  took  about  four  days  to  in- 
stall the  equipment,  our  engineer 
remained  on  board  and  finished  the 
work  while  the  ship  was  enroute  from 
Malta  to  the  Dardanelles. 

..ci.-i.i  ;  .,,iu[);i,-Kic.>  on  li'stai^' 
MiifhiiKi  which  sinmlalcs  the 
Holl, Pilch  iinfiYawof  ShipatS<'a 


38 


=t\vrx-i^x-rr^^'^''y^''^'''^  i. 


■n-'tirf  **'**'^''^ 


Gtro-Compass 


-CTHfJTl'ajJM 


The  WluUe-liadi,  itMdkst  of  all  ia  rough  wottlier 

Tliis  ship,  the  Inflexible,  arrived  at  the  Dardanelles  just  in  time  to  join  in  the  first 
naval  action  directed  against  the  land  batteries.  During  the  first  part  of  the  engagement 
our  engineer  remained  with  the  Master  Compass  which  was  installed  near  the  dynamo 
room.  When  he  saw  that  it  was  functioning  properly  he  left  it  to  go  on  deck  and  view 
the  action,  the  efTecls  of  which  he  had  become  aware  of,  as  a  number  of  shells  from  the 
land  batteries  had  hit  the  ship.  Almost  immediately  after  he  arrived  on  deck  a  torpedo 
struck  the  ship  directly  under  the  compartment  where  the  Gyro-Compass  was  located, 
killing  every  man  in  that  compartment.  Although  badly  damaged  the  ship  was  able  to 
get  out  of  range  of  the  land  batteries  and  reach  the  naval  base  near  the  Dardanelles. 

The  Gyro-Compass  was,  of  course,  almost  totally  destroyed.  Shortly  after  the 
action  ended  our  engineer  was  enabled  to  get  ashore  on  a  Greek  island  via  one  of  the 
British  destroyers.  This  island  had  a  telegraph  station  which  he  used  to  cable  us  that 
"Equipment  No.  286  is  under  four  feet  of  water,"  and  that  we  should  have  another 
equipment  ready  to  replace  it.  We  took  this  telegram  to  the  Admiralty  w  ho  authorized 
us  to  have  another  equipment  prepared  to  meet  this  ship  at  Gibraltar.  This  we  did, 
again  sending  a  Service  Engineer  who  met  the  ship  at  Gibraltar,  on  her  way  back  to 
England  to  be  repaired  and  refitted. 

The  Sperr\-  Service  Organization  stands  ready  to  help  all  ships  equipped  with  a 
Gyro-Compass  at  all  times,  even  in  emergencies  such  as  those  experienced  by  naval  vessels. 

Service  Given  to  the  World's  Navies  by  the  Gyro-Compass 

At  the  time  of  the  battle  of  Coronel  on  the  west  coast  of  South  America,  H.  M.  S. 
Invincible  was  being  overhauled  at  the  Portsmouth  Dockyard  in  England.  She  was 
immediately  ordered  with  one  other  large  British  ship  to  South  American  waters  under 
the  command  of  Admiral  Sturdee,  to  re-enforce  the  British  fleet,  and  then  to  find  and 
destroy  the  German  ships  which  had  defeated  the  British  at  the  battle  of  Coronel. 
When  the  overhaul  of  the  Invincible 

was  completed  and  she  was  ready ..^ 

to  leave  the  docks,  it  was  at  first 
planned  to  delay  saiUng  until  the 
ship  could  be  swung  and  the 
magnetic  compasses  compensated. 
It  was  decided,  however,  that  al- 
though the  compasses  were  badly 
in  need  of  adjustment  it  was 
necessary  to  save  every  minute  in 
order  to  reach  South  American 
waters  before  the  German  ships 
could  find  and  destrov  the  British 


ships 


in  those  waters. 


39 


The  S perry 


■■.^.t  ^  1  iTvm.i.i.-i.-.i.t-^7^-5-t^,y-. 


r*yTVsa>.^^^^^  ^"^^'*''^'*^«^*^''^''^'''*'^'*^^^"'^ 


GfRO-COMPASS 


yvKT^r->7l,•^^TIV^^^ll^^Ty^>|lT»^'^^iV>y»^^^»■'  - 


The  Coracle  of  ancimt  Britun,  still  aged  in  Walea 


The  Invincible  therefore  sailed  without  adjusting  her  magnetic  compasses  and  navigated 
entirely  by  the  Sperry  Gyro-Compass  from  Portsmouth  to  the  Falkland  Islands.  When 
an  azimuth  was  finally  taken  the  magnetic  compass  was  found  to  be  out  about  22  degrees. 
The  Invincible  arrived  at  the  Falkland  Islands  just  in  time  to  coal  before  the  German  fleet 
appeared.  If  H.  M.  S.  Invincible  had  not  had  a  Gyro-Compass  the  probabilities 
are  that  she  would  not  have  reached  the  Falkland  Islands  in  time  to  win  the  battle 
which  took  place  almost  immediately  upon  her  arrival. 

Figure  49  shows  a  British  submarine,  a  sister  ship  of  the  E-11,  that  entered  the  Sea 
of  Marmora  through  the  Dardanelles  for  the  purpose  of  destroying  Turkish  and  German 
shipping.  The  E-11  put  a  torpedo  right  into  Constantinople  harbor.  The  Second  Officer 
of  the  E-11  in  relating  this  exploit,  stated  that  they  steered  by  the  "Sperry"  all  the 
way  in  and  out.    His  remark  was  that,  "It  never  let  me  down." 

In  this  exploit,  and  many  others  of  a  similar  nature,  the  Gyro-Compass  was  used 
for  all  navigation.  These  extremely  daring  and  hazardous  operations  would  not  have 
been  possible  without  this  instrument. 

A  similar  British  submarine  left  Harwich  on  the  east  coast  of  England,  and  during 
a  period  of  three  weeks  made  seven  patrol  trips,  and  without  once  seeing  the  sun, 
finally  returned  to  Harwich  and  picked  up  the  buoy  at  the  mouth  of  the  harbor  without  the 
least  difficulty.  The  navigation  in  this  case  was  carried  out  entirely  by  the  Gyro-Compass. 
Figure  54  is  a  photograph  of  H.  M.  S.  Lion,  the  flagship  of  Admiral  Beatty  in  the 
battle  of  Jutland.  This  ship  was  provided  with  the  Sperry  Gyro-Compass  equipment 
early  in  the  war.  During  the  Jutland  engagement  a  fire  broke  out  in  a  magazine  of  the 
Lion  immediately  below  the  two  Master  Compasses  which  were  located  in  one  compart- 
ment. It  became  so  hot  that  the  lead  sheathing  was  melted  off  the  electric  cables  and 
one  of  the  Gyro-Compasses  was  heated  until  its  parts  fused.  Notwithstanding  this 
same  heat  the  other  compass  functioned  throughout  the  entire  action.  Of  the  ships 
engaged  in  the  battle  of  Jutland  practically  all  except  the  destroyers  were  equipped 

with  the  Gyro-Com- 
pass. Every  one  of 
them  performed  per- 
fectly throughout  the 
action  except  in  the 
case  of  the  Lion  on 
which  one  was  des- 
troyed by  fire. 

Hundreds  of  Sperry 
Gyro-Compasses  are 
veterans  of  many 
battles  and  encounters 
under  heavy  gunfire 
and  adverse  conditions. 


40 


The  S perry 


_^     GfRO-COMPASS 


iTcrmn  i  v\m  •  ittmn  1 1 1  nvfmaat 


The  Power  Boat,  siiiull,  able,  reJial 


Stn.-  I 


41 


The  S perry 


Mi.!l.,T.  Jr. 


.,-,s£a^ttvvi  _ 


GfRO-COMPASS      % 


^JC'CHXVggvvv^r.ry>T^■lrt^vr^-r^<Of*^v^t^,w^^^ 


Huge  Dug-Outs  are  used  on  African  rivers 


Ships  Rquipi" 


Xtir^-r^--t^vx-x^f-*Y^r-f-<W,!-*'^^Ty'lf^^  y.-.-f 


42 


The  S perry 


^Qoa 


^ji^lpfyMfv^-CTNTnivs^M^x  t^WTTi?^' 


GfRO-COMPASS 


'"^'^^  ■*  gy  «^  "M  f  y  ffwy^BfOtiet^ffe^fttnfeayrv^'  <fr^^ 


Great  ColUerB  carry  coal  for  the  world's  navies 


43 


The  S perry 


-^v^>cv*.f<;,rt^frfyYT"^ 


%»eedy  loe-boats  provic^  thrilling  winter  sport 


GrRO-COMPASS 


Telegrams  /'"land.     SP 
o  \  Foreign:  9P 


ERIGYCO.  Vic.  London 
gn:  aPERIQYCO.  London. 


Telephone,  73S8  VICTORIA. 


THE    SPERRY   GYROSCOPE    COMPANY,  Ltd. 


NEW    YORK    -    LONDON    -    MILAN    -PARIS 

PETROGRAD     -  TOKIO     -     COPENHAGEN 

STOCKHOLM    -    LA  HAGUE 


15,  VICTORIA  STREET. 

LONDON,  8.  W. 


August  1st.  1916. 


B~3909. 


The  Sperry  Gyroscope  Company, 
NEW  yOHK. 


Gentlemen , 

It  gives  me  very  great  pleasure  to  inform  you  that  my 
Company  has  received  from  Their  Lords  Commissi  oner a  of  the  Admiralty, 
under  date  20th  July,  the  tollowlnK  words  of  commendatlon:- 

"I  am  to  add  an  expression  of  Their  Lordships'  appreciation 
of  the  valuable  assistance  renderi'd  to  the  Admiralty  by 
your  Company  since  the  outbri'ak  of  War,  In  your  very  prompt 
and  efficient  execution  of  the  Important  work  entrusted  to 
you"  . 

I  might  mention  that  this  was  the  first  reoomrtendatlon  gl^^■n 

to  a  private  Firm  by  the  British  Admiralty  for  fifteen  years,  and  had 

to  be  concurred  In  bj-  no  less  than  thirty-seven  Government  Officials. 

Very  truly  yours, 

THK  SPEREY  GYBOSCOPE  CC»1PAN7  LTD. 


Managing  Director. 


:«:^ 


C.jyyy»vv^f*viT<v^r<^ 


44 


